Where sound is made on System 9 and System 11/11A
On System 9 and System 11/11A the CPU board has its own sound section (a separate 6808 with a 6821 PIA and amplifier), and an extra board adds speech or more sounds. System 9 uses a large ribbon cable to its speech board; System 11 a smaller one.
Systems
Related tips
- No sound after board work: 1J15 and 1J16 swapped (they aren't keyed)
- Testing the CPU board sound section with Leon's sound EPROM
- System 9 CPU and sound test EPROMs
- CPU sound diagnostic switch SW1 results
- Which System 11 CPU boards fit which games
- No sound from SW1 although sounds play in diagnostics
- System 9 versus System 11 display data
- How System 11 makes sound
Source: Repairing Williams System 11 Pinball 1986 to 1990, Part Three, Clay Harrell